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Project FJ40

Since I bought my 78
FJ40, I have been trying to improve its off-road performance and its on-road
comforts. The more I wheel it, the more I want to improve it. Not
only is this Land Cruiser my trail rig, but sometimes it is my daily driver.
I do not have a tow vehicle for it (yet), so this rig has to be driven to the
trail, through the trail, and back from the trail without any problems.
Therefore, the main goal of Project FJ40 ? ROK
CRZR is to make it into a bulletproof rock crawler
without sacrificing reliability and on-road handling.The Cruiser I started with:a nearly stock December 1978 FJ40

Suspension
Upgrades:After 20 years of use, the stock
leaf springs have sagged to the point of being almost flat. While a flat
spring provides excellent articulation, they do not provide much in the way of
tire clearance. My Cruiser currently has an aftermarket shackle reversal
kit that has really improved the freeway handling, but is not so good in the
rocks. It hangs down a few inches from the frame and I am constantly
banging it into rocks. More lift will help out some, but not enough.
Another problem with my suspension is the leaf springs mount below the axles
which greatly reduces ground clearance. I plan on doing a spring
over conversion which will mount the leaf springs on top of the axles and
provides close to 6 inches of lift. No more springs and u-bolts to get
caught on the rocks. I will also redesign the shackle reversal so it
still hangs down from the frame some. I am also planning on moving the
rear axle back a few inches and install some longer leaf springs to add some
more flex. I am not too sure on the exact suspension set up yet, but
either way, I will still have to have enough lift to clear much bigger tires.

Wheel and Tire
Upgrades:The easiest way to gain ground
clearance is to install larger diameter tires. When you install bigger
lift kits to make room for these bigger tires, you must also think about
installing wider tires to make the vehicle more stable. I plan on
replacing my worn out 33x12.50 mud tires with some 38.5x14.5x15 Super Swamper
TSL SX tires. In order to get more sidewall flex out of the stiff SXs and
help protect from punctures, I will have to air them down very low. To
help prevent blowing the bead on when aired down I plan on installing some
custom 8 lug, 15x10 inch beadlock rims. These may have to be custom made
with the correct backspacing (about 3") so the tires to not rub on the
body, suspension, or steering components while 'wheeling.

Axle Upgrades:Wider is better! Since I am
planning on running much larger tires and lift, I feel that I need stronger
axles and a wider stance. Probably the weakest link on Toyota Land
Cruisers is the Birfield joint in the front axle. I really don't think it
can handle the 38" tall tires. There are a few stronger aftermarket
axle shafts, but you still end up with a CV style joint in the front axle.
Since I want to avoid the Birfield joint all together and swap in wider axles I
must look for a non-Toyota axle. I have decided to swap in a Reverse Cut
Dana 44 which will be a custom width. This axle will have a more ground
clearance, the pinion will exit above the centerline of the axle shafts, more
drive shaft clearance, and no Birfields! Reverse cut gears are stonger in
the front end than standard cut gears when going forward since they are driving
on the drive side of the ring gear and not the coast side. If I have a
problem with breaking front axles or u-joints, I will swap in some alloy axle
shafts.

The rear axle will be a full
floating Dana 60 heavy duty model. Since the Dana 60 rear axle has a
centered differential, I will have to change my transfer case to a Dana 300 or
an Atlas II which both have a centered output yoke. The stock Cruiser
transfer case has an offset output yoke to line up with the off set rear axle.
The benefits of a full floater axle is the load is carried only by the wheel
bearings and not the axle shaft like a semi-floating axle. If I happen to
snap a rear FF axle shaft, I can keep driving without having to worry about the
rear wheel fall off! For the utlimate beef, I want to install some 35
spline, 1.5" alloy axle shafts. I should never have to worry about
breaking one of these.

Getting traction to all 4 wheels
is a must when wheeling. Crossing ruts and climbing rocks with open
differentials can be a bit scary at times. I plan on installing an ARB
Locker or Detroit Locker in the front, and a Detroit Locker or a spool in the
rear. I feel the benefits of a manual locker such as the ARB will be a
huge advantage with the D44 front axle. Being able to turn it off will
help minimize the breakage of the front axle shafts and u-joints. It will
also help save the steering system by allowing the wheels to turn easier when
turned off (ever try to steer a rig with a front locker?). The Detroit
Locker is known for being practically bulletproof. This is a great choice
for rear axle applications. However, a spool may be a better solution
since it has less parts and is always LOCKED. Some people say that you get
more predictable handeling since you know it won't unlock and lock causing the
vehicle to sway in certain situations. I am not too sure on what gear
ratios I will run. This will depend on wich motor, tranny, and t-case I
run. I will most likely run 5.13 gears.

Drive train
Upgrades:In order for a rig to be a good
rock crawler, it needs to have super low gears. The lower the overall
gearing (crawl ratio), the more control the driver has while negotiating tough
obstacles. The crawl ratio is calculated by multiplying the tranny's
first gear by the transfer case's low range by the axle gears. The overall
crawl ratio in my Land Cruiser is 3.55 x 1.95 x 4.11 = 29:1. This is way
too fast for hard core trails that I want to run. Installing a granny
geared transmission like the SM420 with its 7.05:1 first gear will drastically
improve my crawl ratio from 29:1 to 57:1. To further lower my crawl
ratio, I can install one of the earlier Land Cruiser (pre '74) transfer cases
with its 2.3:1 low to get a crawl ratio of 67:1. While 67:1 is a very
respectiable crawl ratio, it really doens't cut it when you factor in larger
tires and larger bolders. A better setup would be to to swap in a centered
output Dana 300 (2.6:1 low) or Atlas II (4.3:1 low) and that would get me about
75:1 or even 125:1 overall crawl ratio with 4.11s.

Motor Upgrades:The stock 2F motor already has
plenty of torque for rock crawling, but it lacks horsepower for normal street
driving. With the addition of bigger tires, the street performance has
lots to be desired. A smog legal header and better flowing exhaust system
will help out somewhat. However, a 350 TBI swap would be the best solution
to improve street performance and it will continue to run in those really off
camber situations where carburetors tend to flood. An added benefit to a
V8 swap is that I will gain some rear drive shaft length since I will be able to
move the tranny and t-case forward a few inches. Another cheaper
alternative is to add an aftermarket fuel injection kit to the 2F motor.
There are a few kits out there now, but none of them are smog legal in
California. I guess I will just wait and see. Also, a high torque
gear reduction starter will help out when the motor and gears just can't cut it.

Protection
Upgrades:Protecting the Cruiser's vitals is
a must no matter how easy the trails are. You never know when you might
slip off a rock and hit your transfer case, transmission, or even land upside
down. A full roll cage is a must if you plan on taking your hard top off.
A transmission and transfer case skid plate is necessary as well as a flat belly
pan to help skid over the rocks. To help protect the body, I plan on
installing some sort of rocker panel protection and quarter panel protection.

Body Upgrades:Since I am going to be running
bigger and wider tires, I will have to add rear fender flares to keep those big
meats covered. I really doubt I will find fender flares to cover the wider
axles and tires so I will probably have to make some kind of quick disconnect
mud flaps to keep it somewhat legal on the street. I really want to take
the hard top off of my Cruiser so I do not damage it too much. And it is
always cool to drive without the top on anyway. I will have to get a
bikini top for the summer months and a soft top for the winter months.
Half doors will also be a great addition for the trail allowing the driver and
passenger to get a better look at the terrain.

My stock rubber body mounts are
nearly flat and showing their age with cracks. It is time to convert over
to polyurethane body mounts. The body mounts help isolate the body from
the noises transmitted through the frame. I also want to add some
type of spray or paint on tub liner or maybe a carpet kit to help out with road
noise.

Accessories:A Saginaw power steering conversion
is going to be one of the major improvements to my Cruiser. There are many
unnecessary links and tie rod ends in stock steering system that can be
eliminated with the Saginaw conversion. A rear bumper with a beefy
swing out tire carrier and gas can holder will be a must since the stock tire
carrier was not designed to carry a full size spare (36-38 inches). It
will also have to have some kind of recovery gear mounted to it since the stock
bumper does not. I plan on adding a Warn 8274 winch that will also require
a heavy duty front bumper. Dual batteries will have to be added just in
case the alternator can not keep up with the current demands from the winch.

An on-board welder will be a
great asset on the trail in the event when something breaks and there are no
spares to be found. I have witnessed quite a few situations where a welder
had saved the day. An on-board air system will also be a great asset on
the trail so you can run air tools, re-seat tire beads, dry off wet components,
actuate ARB lockers and fill up tires at the end of a trail run. One not
so important trail accessory is the hot water shower. This will not get
you unstuck, but it will sure get you clean after a hard day on the trail.

My gas tank will hold about 16
gallons and at 12 MPG, my freeway range is not so great. Last year on the
Rubicon trail, I had to borrow about 5 gallons of gas just to get out. An
auxiliary fuel tank will greatly improve my freeway range and let me go farther
into the outback. With the addition of two more family members (two yellow
Labradors ? Toby and Roxy), more storage area is needed so the four of us can
fit. A roof rack, roll bar rack, center console, and other clever space
saving storage goodies will have to be added to make the already limited cargo
area a wee bit bigger. I will probably look into getting one of those M416
? ton military trailers or just figure out how to carry less gear (yeah right).

And to make getting to the
trails a little more comfortable, new bucket seats and stereo system of some
kind would be nice. I will also have to add a means of communication both
on and off the trail ? a CB radio.

I am sure I will add many other
little things along the way that I have not thought about yet, but I will add
them as I think of them. I hope this project will enlighten others to the
way I have modified my Cruiser and the results I achieved every step of the way.